Field of the Invention
The present disclosure generally relates to back scattering imaging technologies, and in particular, relates to a mobile back scattering imaging security inspection apparatus and a method for performing mobile back scattering imaging security inspection.
Description of the Related Art
A conventional mobile X-ray back scattering inspection apparatus for performing an inspection of an interior of an object such as a vehicle typically includes a ray source and a set of detectors. The ray source is typically a single target source with a large spread angle, rays from which are formed into a pencil beam by a rotation modulation mechanism to perform a point by point scanning operation on a surface of the object to be inspected. The detector has a certain spatial dimension to receive scattering signals in a relatively large spatial range.
In the conventional mobile X-ray back scattering inspection apparatus, a flying spot scanning mechanism configured to modulate the rays to form scanning flying spots is typically a wheel-type flying spot scanning mechanism. By providing a roller wheel provided with a modulation aperture around the source, the pencil ray beam is formed. The pencil ray beam is used for one dimensional scanning operation on the surface of the object to be scanned as the roller wheel rotates. In the apparatus using the wheel-type flying spot scanning mechanism, dimensions and spatial distribution of the ray spots formed by the flying spot mechanism on the surface to be inspected change, in particular have a distortion at the large spread angle, as a modulation spread angle varies. Thus, the spread angle of the ray source is limited. Also, in order to ensure an imaging range, there is a certain requirement for a distance between the ray source and the surface of the object to be scanned.
Furthermore, for an integral mobile system formed by coupling the ray source and the detector, the distance between the ray source and the object to be scanned must influence the distance between the detector and the object to be scanned. An increase in the distance between the detector and the surface of the object to be scanned will influence the spatial coverage of the detector.
In view of the above, it is desired to propose a novel mobile X-ray back scattering imaging apparatus and method.